Quantum computers are not analog computers. They are very much digital. A better analogy is with probabilistic computers: classical probabilistic computers are

Quantum computers are not analog computers. They are very much digital. A better analogy is with probabilistic computers: classical probabilistic computers are digital computers with a source of random bits. Quantum computers are digital computers in which randomness is governed by quantum probability amplitudes, not by classical probabilities. It is more fruitful to think of quantum computers as digital computers governed by a different, non-classical generalization of probability theory.